Characterized as a medium-sized venomous pit viper within its genus, with adult lengths typically ranging between 60 and 90 centimeters, although exceptional female specimens can reach up to 120 centimeters. Its body is robust, slightly compressed laterally, with a distinctly triangular head that is well-differentiated from the neck due to the presence of small, irregular cephalic scales. The snout is acute, displaying a highly prominent heat-sensitive loreal pit located between the nostril and the vertically elliptical eye. Its dorsal ground coloration varies from light gray to tan or ocher-brown, featuring a highly characteristic pattern of dark brown trapezoidal or inverted C-shaped blotches arranged alternately or oppositely along the middorsal line, bordered by a thin whitish outline. The ventral region is generally whitish or yellowish, densely speckled with dark gray pigments. It possesses strongly keeled dorsal scales and a solenoglyphous venom delivery system, consisting of long, hollow, retractable fangs located at the anterior portion of the upper jaw.

Geographical distribution: Primarily found in the southern regions of South America. Its geographic range covers vast territories of northern and central Argentina, spanning provinces such as Chaco, Formosa, Santiago del Estero, Tucumán, Salta, Jujuy, Catamarca, La Rioja, San Juan, Mendoza, San Luis, Córdoba, Santa Fe, Entre Ríos, Corrientes, La Pampa, and northern Río Negro. Additionally, its presence is well-documented within the Paraguayan Chaco, adjacent areas of southwestern Bolivia, and localized sectors of southernmost Brazil, particularly in the state of Rio Grande do Sul.

Habitat: Inhabits xerophytic, semi-arid, and temperate terrestrial ecosystems. It is a characteristic resident of the dry Chaco woodlands, wooded savannas, shrubby steppes, high-altitude grasslands, rocky slopes, and transitional ecotones. The species exhibits remarkable ecological plasticity, successfully colonizing anthropized environments such as roadsides, dry agricultural fields, and cattle pastures. It generally avoids dense, humid rainforests and permanent wetlands, preferring well-drained soils and microhabitats that offer natural shelters like fallen logs, abandoned rodent burrows, and rock crevices for thermoregulation and predator avoidance.

Feeding: Exhibits a strictly carnivorous diet that undergoes a pronounced ontogenetic shift. Juvenile individuals rely heavily on ectothermic prey, actively hunting anurans and small lizards. To lure these targets, juveniles utilize caudal luring, waving their lighter-colored tail tip to mimic a wriggling worm. Upon reaching adulthood, their diet transitions almost exclusively to endothermic vertebrates, preying primarily on small rodents from the Caviidae and Cricetidae families, alongside small marsupials and occasionally ground-nesting birds. They capture prey using an ambush strategy, delivering a swift bite to inject venom and subsequently tracking the scent trail of the envenomated animal once it succumbs to the toxins.

Behavior: Primarily terrestrial, showing marked crepuscular and nocturnal activity, especially during the warm spring and summer months, while displaying diurnal activity during cooler transitional seasons to bask in the sun. It is a solitary species that spends most of the day concealed beneath leaf litter or debris. During the coldest months of the austral winter, it enters a state of torpor or brumation in underground shelters protected from frost. Its temperament is highly irritable; when threatened, it assumes a classic S-shaped defensive posture, rapidly vibrates its tail against dry leaves to produce a warning rustle, and delivers swift, precise defensive strikes if the intruder breaches its safety perimeter.

Reproduction: It is a viviparous species, meaning females gestate embryos internally and give birth to fully developed, free-living young. The reproductive cycle is seasonal, with mating typically occurring in early spring after emerging from winter dormancy. The gestation period lasts several months, heavily influenced by environmental temperatures that the female actively regulates through heliothermic behavior. Births are concentrated in late summer and early autumn, yielding litters that usually range from 4 to 18 neonates. The young are born measuring between 15 and 20 centimeters in length, equipped with a fully functional venom apparatus that is active from their very first moments of life.

Conservation status: Categorized under a conservation status of Least Concern (LC) on global and regional red lists, owing to its extensive geographic distribution and relative tolerance to minor anthropogenic landscape alterations. However, local populations face localized pressures due to habitat loss, fragmentation, and degradation caused by agricultural expansion and deforestation. Furthermore, this taxon is subject to intense direct persecution by local human populations because of its highly venomous nature, resulting in high mortality rates driven by fear of snakebite accidents.